From the viewpoint of interaction between medium and incidence electromagnetic wave, the extinction section of fiber coated nickel was estimated by method of electromagnetic field numerical simulation. It was researched that extinction changed with material properties, including aspect ratio of fiber, conductivity, refractive index, and dielectric constant. The results showed parameter regions corresponded to mutation of extinction section. Aspect ratio of fiber influenced the extinction section, especially at middle-near infrared frequency. While aspect ratio was 20-200, image of refractive index was smaller than 20 and real of conductivity of ceramic fiber was 10⁶-10⁸ s·m^-1, extinction section would be increased rapidly. According to calculated results, nickel coated ceramic fiber was prepared with method of chemistry plating. The extinction coefficients were contrasted between metal coated fibers and uncoated fiber measured by potassium bromide press and smoke box. The data showed that mass extinction coefficient of nickel coated carborundum was enhanced obviously, in far infrared range.